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Finding the Fourth Proportional to 420.07, 629.98 and 159.88

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Solution

The fourth proportional to 420.07, 629.98 and 159.88 is: 239.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.07 : 629.98 = 159.88 : x
  2. Step 2: Convert to fraction form
    420.07/629.98 = 159.88/x
  3. Step 3: Cross multiply
    420.07x = 629.98 × 159.88
  4. Step 4: Simplify right side
    420.07x = 100,721.59
  5. Step 5: Solve for x
    x = 100,721.59/420.07
  6. Step 6: Final answer
    x = 239.77

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.